异丙酚减轻大鼠机械通气所致肺损伤

Propofol attenuates ventilator-induced lung injury in rats

目的探讨异丙酚对大鼠高压力机械通气所致急性肺损伤的影响。方法24只Wistar大鼠随机分为3组（n=8）,采用压力控制机械通气模式通气。A组为对照组,通气模式为PIP=25 cmH2O,PEEP=2 cm H2O;B、C两组为异丙酚组,通气模式同A组,B组输注模式为静注2 mg／kg,继以4 mg·ks^-1·h^-1速度持续输注;C组输注模式为静注5 mg／kg,继以10 mg·kg^-1·h^-1速度持续输注,记录基础时点、1h、2 h、3 h、4 h的MAP、HR和动脉血气。4 h后处死全部大鼠。测量肺组织湿干比、BALF中蛋白含量,观察肺组织病理形态学变化。结果A组MAP、PaO2和pH在4 h时显著降低,与基础值相比有统计学差异（P〈 0．05）,而B、C两组与基础值相比无明显变化。在4h时A组的PaCO2显著升高（P〈0．05）,而B、C两组与基础值相比无明显变化。肺组织湿／干比和BALF中蛋白含量A组亦明显高于B、C两组（P〈0．05）。B、C组间无显著差别。肺组织形态学改变B、C组好于A组,肺组织中性粒细胞浸润程度也较轻。结论异丙酚对机械通气所致急性肺损伤具有保护作用,其机制可能与减少中性粒细胞在肺内浸润有关。

Objective To investigate the effects of propofol on ventilation-induced lung injury （VILI） in rats. Methods Twenty-four anesthetized Wistar rats were randomly divided into three groups （n = 8）. Rats were ventilated with high PIP pattern （PIP = 25 cm H2O, PEEP = 2 cm H2O） for 4 h. Propofol was given in a bolus of 2 mg/kg （group B） or 5 mg/kg （group C）, followed by continuous infusion with speed of 4 mg·kg^-1·h^-1 （group B） or 15 mg·kg^-1·h^-1 （group C）. No propofol was given for group A. MAP and HR were recorded and arterial blood gases were analyzed. Weight ratio of wet and dry lung, protein content in BALF and lung morphological changes were also examined. Results There was no significant difference in MAP, pH, PaO2 and PaCO2 among groups except a decrease in MAP, pH and PaO2, and an increase in PaO2 at 4th hour in group A （P〈0.05）. Lung W/D weight ratio and protein content in BALF were higher in group A （P〈0.05）. Morphological changes and neutrophil sequestration were less in groups B and C. Conclusion Propofol attenuates acute VILI in rats in part by probably inhibiting neutrophils sequestration.